Introduction: The use of continuous positive airway pressure has been shown to improve the tolerance of the apnea test, a critical component of brain death evaluation. The ability to deactivate the apnea backup setting has made apnea testing possible using several conventional mechanical ventilators. Our goal was to evaluate the safety and efficacy of apnea testing performed on mechanical ventilation, compared with the oxygen insufflation technique, for the determination of brain death.
View Article and Find Full Text PDFAn existing chlorophyll-based model has been updated and re-calibrated using measured data describing Jerlov water types, harvested from the World-wide Ocean Optics Database. This study has provided new chlorophyll concentration data, and used them in conjunction with recently published spectra of absorption and scattering coefficients to create an updated parameter set that describes eight of the 10 Jerlov water types. The updated model is consistent with other data, and it interprets the measured characteristics in terms of underlying properties.
View Article and Find Full Text PDFBasilar artery occlusion (BAO) is a rare cause of stroke associated with significant morbidity and mortality. It is most frequently thromboembolic in nature, but may be caused by vertebral artery dissection. We present a case of BAO in a 36-year-old woman with Alport syndrome.
View Article and Find Full Text PDFObjectives: Transcranial Doppler (TCD) has been evaluated as a noninvasive intracranial pressure (ICP) assessment tool. Correction for insonation angle, a potential source of error, with transcranial color-coded sonography (TCCS) has not previously been reported while evaluating ICP with TCD. Our objective was to study the accuracy of TCCS for detection of ICP elevation, with and without the use of angle correction.
View Article and Find Full Text PDFBackground: Family caregivers of patients with severe acute brain injury (SABI) admitted to intensive care units (ICUs) with coma experience heightened emotional distress stemming from simultaneous stressors. Stress and coping frameworks can inform psychosocial intervention development by elucidating common challenges and ways of navigating such experiences but have yet to be employed with this population. The present study therefore sought to use a stress and coping framework to characterize the stressors and coping behaviors of family caregivers of patients with SABI hospitalized in ICUs and recovering after coma.
View Article and Find Full Text PDFMany phytoplankton taxa function on multiple trophic levels by combining photosynthesis and ingestion of bacteria, termed mixotrophy. Despite the recognition of mixotrophy as a universal functional trait, we have yet to fully resolve how environmental conditions influence community grazing rates in situ. A microcosm study was used to assess bacterivory by mixotrophic nanoflagellates following nutrient enrichment and light attenuation in a temperate lake.
View Article and Find Full Text PDFVisual distractions pose a significant risk to transportation safety, with laser attacks against aircraft pilots being a common example. This study used a research-grade High Dynamic Range (HDR) display to produce bright-light distractions for 12 volunteer participants performing a combined visual task across central and peripheral visual fields. The visual scene had an average luminance of 10 cd∙m with targets of approximately 0.
View Article and Find Full Text PDFTraumatic brain injury (TBI) is one of the major causes of disability and mortality worldwide. Rapid and precise clinical assessment and decision-making are essential to improve the outcome and the resulting complications. Due to the size and complexity of the data analyzed in TBI cases, computer-aided data processing, analysis, and decision support systems could play an important role.
View Article and Find Full Text PDFFreshwater ecosystems, including lakes, streams, and wetlands, are responsive to climate change and other natural and anthropogenic stresses. These ecosystems are frequently hydrologically and ecologically connected with one another and their surrounding landscapes, thereby integrating changes throughout their watersheds. The responses of any given freshwater ecosystem to climate change depend on the magnitude of climate forcing, interactions with other anthropogenic and natural changes, and the characteristics of the ecosystem itself.
View Article and Find Full Text PDFInherent optical properties (IOPs) of typical ocean waters have been derived from a worldwide database of measured parameters. The optical quality of the world's oceans can be described in terms of their Jerlov water type, ranging from the clearest Jerlov I to the most turbid Jerlov 9C. These Jerlov classifications are defined in terms of an apparent optical property known as the downwelling diffuse attenuation coefficient ().
View Article and Find Full Text PDFBMC Med Inform Decis Mak
August 2022
Background: Traumatic Brain Injury (TBI) is a common condition with potentially severe long-term complications, the prediction of which remains challenging. Machine learning (ML) methods have been used previously to help physicians predict long-term outcomes of TBI so that appropriate treatment plans can be adopted. However, many ML techniques are "black box": it is difficult for humans to understand the decisions made by the model, with post-hoc explanations only identifying isolated relevant factors rather than combinations of factors.
View Article and Find Full Text PDFBackground And Purpose: A variety of neurological manifestations have been attributed to COVID-19, but there is currently limited evidence regarding risk factors and outcomes for delirium in critically ill patients with COVID-19. The purpose of this study was to identify delirium in a large cohort of ICU patients with COVID-19, and to identify associated features and clinical outcomes at the time of hospital discharge.
Methods: This is an observational cohort study of 213 consecutive patients admitted to an ICU for COVID-19 respiratory illness.
Delayed cerebral ischemia (DCI) occurs during a risk period of 3-21 days following aneurysmal subarachnoid hemorrhage (aSAH) and is associated with worse outcomes. The identification of patients at low risk for DCI might permit triage to less intense monitoring and management. While large-vessel vasospasm (LVV) is a distinct clinical entity from DCI, the presence of moderate-to-severe LVV is associated with a higher risk of DCI.
View Article and Find Full Text PDFCrit Care Explor
September 2021
Unlabelled: To prospectively describe 1-year outcomes, with a focus on functional outcome, cognitive outcome, and the burden of anxiety, depression, and post-traumatic stress disorder, in coronavirus disease 2019 patients managed with extracorporeal membrane oxygenation.
Design: Prospective case series.
Setting: Tertiary extracorporeal membrane oxygenation center in the United States.
The Montreal Protocol and its Amendments have been highly effective in protecting the stratospheric ozone layer, preventing global increases in solar ultraviolet-B radiation (UV-B; 280-315 nm) at Earth's surface, and reducing global warming. While ongoing and projected changes in UV-B radiation and climate still pose a threat to human health, food security, air and water quality, terrestrial and aquatic ecosystems, and construction materials and fabrics, the Montreal Protocol continues to play a critical role in protecting Earth's inhabitants and ecosystems by addressing many of the United Nations Sustainable Development Goals.
View Article and Find Full Text PDFInformation, energy, and matter are fundamental properties of all levels of biological organization, and life emerges from the continuous flux of matter, energy, and information. This perspective piece defines and explains each of the three pillars of this nexus. We propose that a quantitative characterization of the complex interconversions between matter, energy, and information that comprise this nexus will help us derive biological insights that connect phenomena across different levels of biological organization.
View Article and Find Full Text PDFBackground: Cerebrovascular autoregulation (CA) is a protective mechanism that enables the cerebral vasculature to automodulate tone in response to changes in cerebral perfusion pressure to ensure constant levels of cerebral blood flow (CBF) and oxygen delivery. CA can be impaired after neurological injury and contributes to secondary brain injury. In this study, we report novel impedance indices using trans-ocular brain impedance (TOBI) during controlled systemic hemorrhage and hypotension to assess CA in comparison with pressure reactivity index (PRx).
View Article and Find Full Text PDFBackground: Sodium chloride (NaCl) 23.4% solution has been shown to reduce intracranial pressure (ICP) and reverse transtentorial herniation. A limitation of 23.
View Article and Find Full Text PDFWildfire smoke often covers areas larger than the burned area, yet the impacts of smoke on nearby aquatic ecosystems are understudied. In the summer of 2018, wildfire smoke covered Castle Lake (California, USA) for 55 days. We quantified the influence of smoke on the lake by comparing the physics, chemistry, productivity, and animal ecology in the prior four years (2014-2017) to the smoke year (2018).
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